This invention relates generally to gas turbine engines, and more specifically to seal assemblies used with gas turbine engine rotor assemblies.
At least some known gas turbine engines include a core engine having, in serial flow arrangement, a fan assembly and a high pressure compressor which compress airflow entering the engine, a combustor ignites a fuel-air mixture which is then channeled towards low and high pressure turbines which each include a plurality of rotor blades that extract rotational energy from airflow exiting the combustor. The high pressure compressor is coupled by a shaft to the high pressure turbine.
At least some known high pressure turbines include a first stage disk and a second stage disk that is coupled to the first stage disk by a bolted connection. More specifically, the rotor shaft extends between a last stage of the multi-staged compressor and the web portions of the turbine first stage disk. The first and second stage turbine disks are isolated by a forward faceplate that is coupled to a forward face of the first stage disk, and an aft seal that is coupled to a rearward face of the second stage disk web. An interstage seal assembly extends between the first and second stage disks to facilitate sealing flow around a second stage turbine nozzle.
At least some known interstage seal assemblies include an interstage seal and a separate blade retainer. The interstage seal is coupled to the first and second stage disks with a plurality of bolts. The blade retainer includes a split ring that is coupled to an axisymmetric hook assembly extending from the turbine stage disk. However, because the seal assemblies are complex, such interstage seal assemblies may be difficult to assemble. To facilitate reducing the assembly time and costs of such seal assemblies, other known interstage seal assemblies include an integrally-formed interstage seal and blade retainer. More specifically, such seal assemblies use radial and axial interference to transmit torque from the stage two disk  to the stage one disk. However, because such seal assemblies are coupled between the turbine stage disks with radial and axial interference fits, such seal assemblies may be susceptible to low cycle fatigue (LCF) stresses induced from one or both turbine stage disks.